As technologies develop, a rate of an Ethernet develops from 10 megabit/s (megabit/s), 100 megabit/s, 1 gigabit/s (gigabit/s), and 10 gigabit/s, to 40 gigabit/s and 100 gigabit/s. With rapid development of Internet Protocol (IP) videos and cloud computing, service traffic increases by 50% to 80% every year. This drives the Ethernet to evolve towards a higher rate. An Ethernet (collectively referred to as a next generation Ethernet in this application) with a rate greater than 100 gigabit/s may have a rate of 400 gigabit/s, 1 terabit/s (terabit/s), or 1.6 terabit/s.
As a rate of an Ethernet interface increases, a bandwidth of a single channel is hardly greater than 100 gigabit/s. To enable a bandwidth of the Ethernet interface to exceed 100 gigabit/s, a multichannel becomes an optional manner. If a transmission rate of the single channel is increased, a transmission loss phenomenon is introduced, and a bit error occurs during data transmission. Therefore, for the next generation Ethernet interface, to enable a receiver circuit to correct an error that occurs in a data transmission process, a forward error correction (FEC) mechanism is introduced.
In an existing physical layer architecture of an Ethernet interface of 40 gigabit/s and an Ethernet interface of 100 gigabit/s, to correct an error introduced during long-distance transmission, a high-gain FEC mechanism is used. However, physical-layer resources of an Ethernet interface are increased in the high-gain FEC mechanism.